Page 345 - Civil Engineering Formulas

276 CHAPTER ELEVEN

PI
I
E T T

M PC PT

I C
2
R R
I

I
2
FIGURE 11.1 Circular curve.

a
C
b
C

d d

FIGURE 11.2 Offsets to circular curve.

Equations of Circular Curves
5,729.578 exact for arc definition, approxi-
R (11.1)
D mate for chord definition
50
exact for chord definition
1
sin 2 D
1
T R tan 2 I exact (11.2)
1
1
E R exsec 2 I R (sec 2 I 1) exact (11.3)
1
1
M R vers 2 I R (1 cos 2 I) exact (11.4)